As a technique regarding a vehicle ventilator, which aims at “simplifying structure to reduce labor in manufacturing, securing appropriate air quantity and air speed while maintaining predetermined air conditioning performance, and reducing noise”, there has been proposed a vehicle ventilator provided with: a first duct arranged in the upper part of a vehicle so as to supply conditioned air from an air conditioning means into a cabin; a second duct arranged in the lower part of the vehicle so as to suck air inside the cabin for returning; a third duct arranged in the lower part of the vehicle so as to suck air inside the cabin for leading it to an exhaust means; an air conditioning means arranged under the floor so as to mix return air from the second duct with air from outside the cabin sucked in by suction means for air conditioning; and ventilation means including the suction means and exhaust means, wherein when the inside of the cabin is partitioned, independent ventilation means are provided for respective compartments and the third duct is connected to an exhaust port of a lavatory” (Patent Document 1).
Further, as a technique regarding a vehicle air conditioner, which aims at solving a problem that “in a vehicle air conditioner using flammable refrigerant, leaking refrigerant cannot be sometimes discharged to outside by a fan device and there is fear that the refrigerant may be leaked from an internal air introduction port into a cabin even if a door of an air delivery device is closed”, there has been proposed a vehicle air conditioner “having a configuration in which a concentration of the flammable refrigerant is prevented from arriving at a combustion range by increasing an external air introduction amount when the leakage amount of the flammable refrigerant is small and when the leakage amount of the flammable refrigerant is large, air conditioned air blowout ports 11, 12, 13 and an internal air introduction port 3 are closed to thereby completely isolate the inside of a casing 2 from the inside of the cabin and the operation of a compressor 19 is stopped” (Patent Document 2).